Chronic, excessive alcohol consumption can result in thiamine deficiency, which affects the central nervous system and can lead to what is termed Wernicke-Korsakoff syndrome (Anderson et al 2002; Kolb & Whishaw 2003; Lopatko et al 2002). Wernicke’s disease is the acute phase of the syndrome, which results in damage to the sixth nerve, causing nystagmus (involuntary, rhythmic movement of the eyes), ataxia (staggering gait) and confusion. This is reversible with thiamine therapy. Korsakoff’s psychosis is the chronic phase of the syndrome, resulting in short-term memory loss and confabulation (Kolb & Whishaw 2003). Recovery from this syndrome is usually incomplete. Irreversible alcoholic dementia may also occur (Ambrose, Bowden & Whelan 2001).

Approximately 2% of the total burden of disease in Australia can be attributed to illicit drug use. In 2004, over one-third (38%) of the population aged 14 years or over had at some time used an illicit drug (AIHW 2004). Studies over the past decade suggest that 40–50% of Australians and New Zealanders have tried cannabis at least once and that most people who use cannabis do so only occasionally. Approximately 10–20% of New Zealanders use cannabis regularly (Fergussen & Holmwood 2000). In 2004, one in three Australians had used marijuana. In 2004, this equated to almost 2 million Australians who had used cannabis recently (AIHW 2004). According to Todd et al (2002), rates of cannabis use and dependence appear higher in New Zealand Māori than in New Zealand non-Māori, with rates of dependence approximately 1.8 times higher (Todd et al 2002).

It is estimated that approximately 100,000 Australians inject drugs regularly and an additional 175,000 inject drugs occasionally. New Zealand has approximately 30,000 drug injectors. In Australasia the number of injecting drug users is estimated to have doubled every 10 years since the 1960s, with heroin or amphetamine being the most frequently injected drugs in Australia, and opioids such as morphine and home bake (extracted from codeine tablets) the most frequently used in New Zealand (Australasian Society for HIV Medicine 2001). Injection of illicit drugs and non-prescribed pharmaceuticals can have adverse health effects including drug overdose and acquiring of blood-borne infections (such as hepatitis C virus (HCV) or HIV). While hepatitis C prevalence among injecting drug users is high (50–60%), in the general population it is only 2% (AIHW 2004).

Substance use and misuse among Indigenous Australians

Aboriginal and Torres Strait Islander people suffer a much greater burden of ill health than other Australians, and they continue to be disadvantaged across a range of socioeconomic factors that have an impact on health (AIHW 2004). The most prevalent substance used by Aboriginal and Torres Strait Islander people aged 12 years or over in 2004 was alcohol. Although there is considerable regional variation, the percentages of Indigenous Australians who have never drunk alcohol or who drink occasionally are roughly the same as for non-Indigenous Australians. However, among regular drinkers the percentage who drink at hazardous levels is higher than in the non-Indigenous population (Hunter, Brady & Hall 2000). Moreover, as a consequence of the relatively higher frequency of hazardous consumption, Indigenous Australians account for a higher number of hospital bed-days per person. Tobacco use is approxi mately twice as high among Indigenous than non-Indigenous people and accounts for approximately 13% of deaths among Indigenous people (Gray et al 2002).

Fifty per cent of Indigenous Australians have reported using cannabis, compared to 40% of non-Indigenous Australians. Overall, illicit drugs account for less than 1% of deaths. However, there has been an increase in the number of Indigenous Australians being admitted for problems such as cannabis misuse, amphetamine misuse and drug-induced psychosis (Gray et al 2002). In some small rural communities in central and northern Australia, the inhalation of petrol fumes is a serious problem. Prior to the introduction of unleaded petrol and aviation fuel in remote communities, lead poison ing was a major health problem for petrol sniffers. Although this problem has been alleviated, the inhalation of other solvents such as aerosols remains a significant issue for some communities (Gray et al 1995, 2002; Gray, Sputore & Walker 1998; Hunter Brady & Hall 2000).

In June 2007 a report was released detailing widespread sexual abuse in some remote communities in the Northern Territory. The report states that of all the social factors involved, alcohol is the greatest threat to child safety and that drastic efforts are needed in order to reduce alcohol consumption (Wild & Anderson 2007).

Substance use and misuse among New Zealand Māori

In common with Indigenous Australians, alcohol use among New Zealand Māori indicates that compared to the general population, fewer Māori than non-Māori drink (Hutt 2004). Those who do drink, do so less frequently but consume more on each occasion (Adamson et al 2000; Ministry of Health 2002). After alcohol, nicotine is the most commonly used drug, with percentages of smokers estimated to be as high as 50% of women and 35% of men (Robertson et al 2002). Cannabis use is viewed by some as being more prob lematic for Māori due to the favourable cultivation climate and the socioeconomic status of some Māori. A recent survey indicated that 60% of Māori had used cannabis at some time, and that 18% were regular users (Dacey & Moewaka Barnes 2000) and that Māori cannabis users are over-represented in AOD services. Benzodiazepine use is also increasing among Māori, and solvents continue to be used among some young, usually male, sections of the population (Dacey & Moewaka Barnes 2000).

Pregnant and/or breastfeeding women

The 2004 National Drug Strategy survey found that women who were pregnant or breastfeeding in the previous 12 months were less likely to consume alcohol or any illicit drugs. In addition they were more likely to reduce their tobacco consumption, with 20% of those surveyed likely to continue smoking during their pregnancy (AIHW 2004).

There is evidence that high levels of alcohol consumption during pregnancy can contribute to a variety of adverse outcomes in the newborn child. However, the evidence of the effects on the fetus of drinking lower levels is less clear. Overall, the most consistent evidence to date identifies an average of one standard drink per day as the level below which no discernible evidence has been found of harm to the unborn child (Royal Women’s Hospital 2005).

Pharmacology of psychoactive drugs

The World Health Organization (WHO) uses the term ‘drug’ to describe a chemical entity used non-medically and self-administered for its psychoactive effect. The psychoactive effect is an essential component of the description and usually includes a change in mood, arousal and/or perception, cognition (thinking) and/or behaviour (WHO 2004b).

All psychoactive drugs have the capacity to produce drug dependence. These drugs may be produced in a laboratory (e.g. amphetamines or ecstasy) or extracted from plants (e.g. heroin or cocaine). They can also be legal (such as alcohol) or illicit (e.g. cannabis). Psychoactive drugs can cause harm either through intoxication or through dependence (Whelan 1999). They can be classified in many ways. One of the most common methods is to classify them as depressants, stimulants or hallucinogens. Some drugs have multiple actions and therefore can be placed in more than one category (Teesson & Hall 2001).

Depressants are drugs that slow down the activity of the brain. When used in small doses they produce relaxation or drowsiness; in larger doses they produce a loss of consciousness similar to a deep sleep. Some can produce impaired coordination, depression and, in large quantities, coma and death. Depressant drugs include ethanol (alcohol), benzodiazepines (e.g. diazepam), sleeping tablets (e.g. Normison^®), opioids and painkillers (e.g. codeine, morphine, heroin), and solvents and inhalants (e.g. petrol, nitrous oxide, amyl nitrate) (National Institute on Drugs and Alcohol (NIDA) 2007; Teesson & Hall 2001).

Stimulant drugs accelerate activity in the nervous system and increase the body’s sense of arousal. In small doses they increase awareness and concentration and decrease fatigue. Irritability, activity, nervousness and insomnia increase as the amount taken increases, and some individuals experience delusions and hallucinations. Excessive doses can lead to convulsions and death. Stimulants include amphetamines (commonly known as speed), methamphetamines (commonly known as crystal meth, ice), d-amphetamine (dexamphetamine) and methylphenidate (Ritalin^®). Other stimulant drugs include cocaine, nicotine, caffeine and 3,4 methylenedioxymethamphetamine (MDMA, commonly known as ecstasy) (NIDA 2007; Teesson & Hall 2001).

Hallucinogens (also called psychedelics or psychotomimetics) share properties with both of the previous categories. However, their specific function is to distort perception and consequently induce hallucinations (auditory, tactile and/or visual). In small doses, some hallucinogens such as cannabis reduce inhibitions and cause the user to become more relaxed and feel more sociable. Hallucinogens include lysergic acid diethylamind (LSD), psilocybin (magic mushrooms) and mescaline (part of the Mexican cactus, peyote). Some amphetamine derivatives such as MDMA (ecstasy) are chemically related to mescaline and have both stimulant and hallucinatory properties and may be placed in both categories for classification purposes (NIDA 2007; Teesson & Hall 2001). In 2004, approximately 1.2 million people had used ecstasy (National Drugs Strategy 2004).

Although cannabis is commonly placed with the hallucinogenic group of drugs, it is often difficult to classify in pharmacological terms as it has a mixture of mood, cognitive, motor and perceptual effects and does not clearly belong with any one drug class (Ashton 2001). In 2004 there were almost 2 million Australians aged 14 years and over who had recently used cannabis (National Drugs Strategy 2004).

How do drugs work?

The effects of drugs on the body can be understood through two concepts: pharmacokinetics and pharmacodynamics.

Pharmacokinetics is the study of the action of drugs within the body, including the mechanisms of absorption, distribution, metabolism and excretion (Anderson et al 2002). The pharmacokinetics of each drug differs; for example, the oral administration of amphetamines produces peak cardiovascular effects after approximately one hour, while central nervous system (CNS) effects peak about two hours after administration. The effects last for 4–6 hours. However, if the drug is admin istered intranasally (snorting), the effects are felt within a few minutes. Intravenous injection produces even faster results. Amphetamines are eliminated by metabo lism in the liver and excreted by the kidneys, and much is excreted as unchanged amphetamine (Latt et al 2002).

In comparison, smoking cannabis delivers the active ingredient tetrahydrocannabinol (THC) rapidly to the blood and brain. Plasma THC peaks at the end of smoking (approximately 14 minutes) and falls to low values within two hours. If cannabis is consumed orally, its absorption is lower and its effects are more variable and also often less pronounced. THC is fat-soluble, which results in a slow elimination of metabolites, and it can be detected in the urine several days after administration and well after the acute effects of THC have disappeared (Todd et al 2002).

Pharmacodynamics is the study of how a drug acts on a living organism, including the pharmacological response and the duration and magnitude of response observed relative to the concentration of the drug at an active site in the organism (Anderson et al 2002). As with pharmacokinetics, each drug action is different; for example, amphetamines activate the CNS and have peripheral sympathomimetic actions. The CNS stimulation results in euphoria, an increased feeling of wellbeing, increased energy and confidence, improved cognitive and psychomotor performance, insomnia and suppression of appetite. Sympathomimetic effects include elevated blood pressure and tachycardia (Latt et al 2002).

In contrast, the effects of cannabis are mediated by the actions of THC at CB1 receptors in the brain and peripheral tissues (e.g. endothelial cells and testes). Cannabis taken in low doses produces a mixture of stimulatory and depressant effects; at high doses the effects are mainly depressant. The effects of cannabis include euphoria, relaxation and a feeling of wellbeing. In addition, there are perceptual distortions such as altered time sense. Memory, cognition and skilled task performance are impaired, although many users may feel confident and highly creative. Peripheral effects include tachycardia, vasodilatation and hypotension. Cannabis stimulates the appetite and is also an antiemetic, and people who have taken cannabis often experience ‘the munchies’ when they feel hungry and crave certain foods (Todd et al 2002). As with all psycho active drugs, the effects vary between individuals depending on the amount taken, the manner of administration, the frequency of use, concurrent use with other drugs, past exposure and the environment in which the drug is used.

Core diagnoses for substance use

Substance use exists on a continuum that extends from abstinence through intermittent non-hazardous (and sometimes beneficial) use, risky or hazardous use, and harmful use, to dependence (Saunders & Young 2002). In general, the greater the frequency of use and the greater the amount of AOD consumed per occasion, the more severe the consequences for the user’s health, the psychosocial consequences and the risk of dependence. However, problems may occur due to occasional, high-level (binge) use, and/or repeated harmful but not dependent use. The terms substance abuse and dependence can be difficult to define precisely, as there are extraneous factors that must be taken into account, such as culture and ideology. For example, in some cultures the use of psychoactive drugs for religious or spiritual ceremonies is accepted but in other cultures is prohibited. The evidence for levels of alcohol consumption is based on a systematic review of international literature commissioned by the National Health and Medical Research Council (NHMRC 2001).

The descriptive terms that are most often used are:

These are discussed on the following pages.

Intoxication

Intoxication occurs when a person’s intake of a substance exceeds their tolerance and produces behavioural and/or physical changes. There is no formally agreed definition, although it is usually taken to refer to an elevated blood alcohol concentration such that a person cannot function within their normal range of physical/cognitive abilities. The DSM-IV-TR criteria for intoxication (see Box 20.1) are used for diag nosis. Women become intoxicated after drinking smaller amounts of alcohol than men, because their smaller body weight, smaller liver size and smaller blood vol ume give a higher concentration of alcohol in their vital organs for a given dose. It is important for nurses to manage intoxication correctly because it complicates assessment and client management, even when it is not life-threatening. Intoxication can be dangerous because it can mimic or mask serious illness or injury (infections, hypoxia, head injury, hypoglycaemia, temporal lobe epilepsy, drug toxicity (Dilantin^®, digoxin), meningitis, cerebral vascular accidents, and transient ischaemic accidents).

Psychoactive drugs affect mood, cognition, behaviour and physiological functioning. Intoxication can be life-threatening because it can cause altered physical functioning (for example, depressed respiration, alterations in temperature regulation and altered mental function such as panic or paranoia, which can result in accidental injuries). The essential feature of substance intoxication is that it is reversible and is due to the recent inges tion of, or exposure to, a substance. The maladaptive behavioural or psychological changes associated with intoxication are due to the direct physiological effects of the substance on the central nervous system and develop during or shortly after the use of the substance. The symptoms are not due to a general medical condition or are not better accounted for by another mental disorder. Intoxication is often associated with substance abuse or dependence, but this category does not apply to nicotine (APA 2000).

Hazardous use

Hazardous use is defined as a repetitive pattern of use that poses a risk of harmful physical and psychological consequences (potential problem). Hazardous substance use is defined in terms of at-risk behaviours such as sharing intravenous needles, bingeing and using substances in unsafe settings, such as when using machinery (Saunders & Young 2002). The NHMRC in Australia defines hazardous consumption of alcohol as a regular daily intake of more than 40 grams for men or more than 20 grams for women.

Harmful use

The term harmful use is used when the pattern of substance use is actually causing harm. Both the Australian NHMRC and the New Zealand definition of harmful alcohol use emphasise high-risk levels of alcohol consumption rather than specific consequences. In Australia this level is over 60 grams per day for men and over 40 grams per day for women. In New Zealand the same quantity is used but is applied to ‘per session’ (Saunders & Young 2002).

Substance abuse

The term substance abuse is often associated with addiction and dependence. It is considered value laden, and has limited use in contemporary addiction literature in the United Kingdom (Hussein Rassool 2002). In Australia and New Zealand the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV-TR) (APA 2000) is used to diagnose substance dependence. It focuses on social and interpersonal consequences of substance abuse, such as failure in role obligations, and recurrent legal, social or interpersonal problems. Substance abuse can therefore be defined as the use of drugs or alcohol in a way that disrupts prevailing social norms, remembering that these norms vary with culture, gender and generation (Saunders & Young 2002).

BOX 20.4 DSM-IV-TR diagnostic criteria for substance dependence

A maladaptive pattern of substance use, leading to clinically significant impairment or distress, as manifested by three (or more) of the following, occurring at any time in the same 12-month period:

1. Tolerance, as defined by either of the following:

• a need for markedly increased amounts of the substance to achieve intoxication or desired effect

• markedly diminished effect with continued use of the same amount of the substance.

2. Withdrawal, as manifested by either of the following:

• the characteristic withdrawal syndrome for the substance

• the same or a closely related substance is taken to relieve or avoid withdrawal symptoms.

3. The substance is often taken in larger amounts or over a longer period than was intended.

4. There is a persistent desire or unsuccessful efforts to cut down or control substance use.

5. A great deal of time is spent in activities necessary to obtain the substance (e.g. visiting multiple doctors or driving long distances), use of the substance (e.g. chain smoking), or recovering from its effects.

6. Important social, occupational or recreational activities are given up or reduced because of substance use.

7. The substance use is continued despite knowledge of having a persistent or recurrent physical or psychological problem that it is likely to have been caused or exacerbated by the substance (e.g. current cocaine use despite recognition of cocaine-induced depression, or continued drinking despite recognition that an ulcer was made worse by alcohol consumption).

Specify if:

• With physiological dependence: evidence of tolerance or withdrawal (i.e. either item 1 or 2 is present)

• Without physiological dependence: no evidence of tolerance or withdrawal (i.e. neither 1 nor 2 is present)

Source: APA, DSM-IV-TR 2000.

BOX 20.3 DSM-IV-TR diagnostic criteria for substance abuse

Source: APA, DSM-IV-TR 2000.

A. A maladaptive pattern of substance use leading to clinically significant impairment or distress, as manifested by one (or more) of the following occurring within a 12-month period:

• recurrent substance use resulting in a failure to fulfill major role obligations at work, school or home (e.g. repeated absences or poor work performance related to substance use; substance-related absences, suspensions, or expulsions from school; neglect of children or household)

• recurrent substance use in situations in which it is physically hazardous (e.g. driving an automobile or operating a machine when impaired by substance use)

• recurrent substance-related legal problems (e.g. arrests for substance-related disorderly conduct)

• continued substance use despite having persistent or recurrent social or interpersonal problems caused or exacerbated by the effects of the substance (e.g. arguments with spouse about consequences of intoxication, physical fights)

B. The symptoms have never met the criteria for this class of substance.

Dependence

Saunders & Young (2002) describe one paradox of substance use, which is the persistent use of a substance despite negative consequences. Often these negative consequences contradict the original motive for substance use in the early stages. For example, a person who is alcohol dependent may have initially used alcohol as a way of coping with anxiety, yet now maintains dependent use despite increased financial, relationship, physical and employment worries. The individual may consider that the reinforcing effects of alcohol use outweigh the negative consequences of its use. Dependence can be both physical and psychological. It is often referred to as a psychobiological syndrome (Saunders, Young & Dore 2001), which exists along a continuum. It consists of a number of behavioural, cognitive and physiological disturbances that cluster together at the same time. The DSM-IV-TR criteria for dependence are presented in Box 20.4.

Assessment and diagnosis

The use of alcohol and other drugs is very common in Australia and New Zealand (as well as other countries) and AOD use must be considered as a possibility with every client that a nurse sees in any setting. Specific assessment tools and criteria are used for a client who presents with a substance disorder or who has a dual diagnosis. Because of the wide variety of substances available and the range of possible use, it is important to carefully elicit an AOD history from the client. The purpose of eliciting information about substance use is to assist in making a diagnosis so that an appropriate management strategy can be developed and implemented (de Crespigny & Cusack 2003). A study undertaken by Carta, Happell & Pinikahana (2002) of 173 mental health professionals, of whom 134 were nurses, found a knowledge and skill gap in assessment and management of AOD problems. Notable knowledge gaps included basic knowledge such as the number of grams of alcohol contained in a standard drink (10) and the number of alcohol-free days per week recommended by the National Health and Medical Research Council (two) (Carta et al 2002).

Presentation, setting and history

The process of assessment will be influenced by the nature of the presentation and the setting. For example, people who present to an emergency department are likely to be distressed due to recent trauma or pain or because family members or friends have been admitted with illness or trauma (Saunders et al 2001). In this setting, the emphasis should be on obtaining key information about the client’s AOD use for their immediate management. The recent substance use history is important in order to assess the type of substance used, and also the level and frequency of use, to identify whether a withdrawal state could occur (Gowing, Ali & White 2000). It is also important in gauging a client’s requirements for analgesia and any potential risk of infection if the person is an injecting drug user.

Information regarding the client’s past AOD use history is also important as this assists in the planning of interventions that may be useful in identifying triggers for using and to prevent relapse. A developmental and family history should be documented as well as identifying the age of first use of each substance used and how its/their use has developed over time. Following on from this, the nurse needs to work with the client to identify when he or she thinks the AOD use became problematic, as well as identifying any periods of abstinence or any change in the use of substances.

Substance use history

A client’s substance use (prescribed and non-prescribed) must be measured to determine whether the level of use may cause harm or whether withdrawal is imminent (Anderson et al 2002). For alcohol there is an agreed low level of consumption, but alcohol interacts with many medications including some herbal preparations. There are too many medications with the potential to interact with alcohol to be listed here, but comprehensive and up-to-date information on alcohol and medication interactions can be found on the MIMS website, which is available through hospitals and health-related libraries that subscribe to the relevant database.

An Australian Standard Drink contains 10 grams of alcohol. Maximum daily alcohol consumption for a person of average or large size should not exceed four standard drinks for men, and two standard drinks for women, and it is advisable to have two alcoholfree days per week (Carta et al 2002). Currently, in

Nurse’s story: working in AOD nursing

The ultimate challenge and ‘high’ of working in AOD nursing is the experience of assisting a client and seeing them creating a happier life out of what is sometimes chaos. My part in providing the information and the skills that help that process of recovery gives me a sense of wellbeing and achievement about what I do. I am only talking about small steps here. Every small step no matter how hesitant is a cause for celebration and joy. You cannot do the client’s work for them but you can provide assistance to them on the journey they must make. That is where skill is needed. The skill is assessing where the client is on the motivational cycle and being able to provide assistance that helps them towards their recovery, yet recognising that everybody has different recovery goals and that each person’s needs are unique. So, the passion for me is in feeling that I am doing something to help people out of this mess. Even if it is only by offering my respect, recognition, skills and time. The downside is that you cannot do it for them, and the struggle with addiction and dependence is a hard and lonely one. At those times when people give up on their goals I remind myself that these problems were a long time developing and will be a long time in being resolved, and that a step back is just that, not the end of the game.

Maureen

(20 years working in AOD nursing in Australia and New Zealand)

Australia, there is debate about whether the number of standard drinks for males should be reduced from four to two drinks daily and whether the advice to women who are pregnant is to be abstinent during pregnancy and while breastfeeding. The Alcohol Advisory Council of New Zealand (ALAC) (it retains the acronym of its former name, the Alcohol Liquor Advisory Council) recommends an intake of less than 60 g of alcohol per day and 210 g/week for men, and less than 40 g/day and less than 140 g/week for women (ALAC 2005). They also recommend that men have no more than six standard drinks in any one sitting and women no more than four. In both Australia and New Zealand there are special circumstances where lower limits of alcohol use or abstention are recommended, such as pregnancy or certain medical conditions. Illicit drugs are more difficult to quantify than alcohol because the same drug can differ vastly from dose to dose in its purity and ingredients.